Barack Obama's first term: the US President's first four years in pictures

October 26, 2012: "The President pretends to be caught in Spider-Man's web as he greets the Nicholas Tamarin, 3, just outside the Oval Office. Spider-Man had been trick-or-treating for an early Halloween with his father, White House aide Nate Tamarin, in the Eisenhower Executive Office Building. I can never commit to calling any picture my favourite, but the President told me that this was HIS favourite picture of the year when he saw it hanging in the West Wing a couple of weeks later."Picture: Official White House Photo by Pete Souza